In a communications system requiring a very high uptime rate, a commonly used topology comprises redundant communications paths (e.g., two physically distinct optical transmission paths) to provide, thereby, a service path and a protection path to form a “1:1” protection system. In the event of a fiber cut or other damage that disrupts data traffic through the service path, the same data traffic may be rerouted through the protection path. In this manner, customer traffic is not interrupted.
In a mesh topology, each of a plurality of network elements or nodes within a communications network is connected to at least two other network elements or nodes. In this manner, a communications path provisioned between a start node and an end node may be satisfied using different groups of intermediate nodes. Thus, in the case of a failure in a communications path between two intermediate nodes, an alternate communications path may be established using other intermediate nodes.